Introduction: Osteoporosis and low bone mass affect millions of people worldwide, leading to severe consequences ranging from disability to mortality. This study aimed to determine the prevalence and risk factors of osteoporosis among postmenopausal women in a district of Nepal.Methods: An analytical cross-sectional study involving postmenopausal women from Nuwakot, Dhading, and Rasuwa districts in Nepal was conducted at Trishuli Hospital, Nuwakot. Ethical approval was taken from the Institutional Review Board of Nepal Health Research Council(Reference number: 1768). The prevalence of osteoporosis was determined, and the associated factors were analyzed using multivariate logistic regression. Dual-Energy X-ray Absorptiometry (GE-Lunar Prodigy) was used to measure Bone Mineral Density (g/cm2) at the proximal femur and lumbar spine. Various factors related to osteoporosis were also analyzed.Results: There were 384 postmenopausal women and the prevalence of osteoporosis was 82 (21.35%; 95% CI: 17.25%-25.45%)e. The mean age of female with osteoporosis was 67.52±8.84 years and that without osteoporosis was 55.70±7.69 years (p <0.001). The multivariate logistic regression showed aOR 0.82 for body mass index.Conclusions: The study reports a lower prevalence of osteoporosis than expected in postmenopausal women. There was a significant inverse relationship between osteoporosis and body mass index. However, no significant association was observed between Bone Mineral Density, biochemical variables, smoking, and parity.